#!/bin/env python
class Student(object):
	@property
	def score(self):
		return self._score
	@score.setter
	def score(self,value):
		if not isinstance(value, int):
			raise ValueError('score must be an integer!')
		if value < 0 or value > 100:
			raise ValueError('score must between 0~100!')
		self._score=value
if __name__=='__main__':
	s=Student()
	s.score=60
	print s.score
